The Warminster Line is a route of the SEPTA Regional Rail commuter rail system. It serves stations between its namesake town, Warminster, and Center City, Philadelphia. Half of the route is shared by other lines, including the Lansdale/Doylestown Line, West Trenton Line, Fox Chase Line, Chestnut Hill East Line, and Manayunk/Norristown Line. The great majority of trains continue as part of the Airport Line.